1. Field of the Invention
This invention relates to an adhesive bonding process for aluminium and/or aluminium alloy and particularly to a process for improving the durability of a bonded aluminium alloy and/or Alclad (Trade Mark) material joint.
2. Discussion of Prior Art
The durability of adhesive bonded joints for aluminium alloy and/or ALCLAD (Trade Mark) materials is critically dependent on the surface treatment applied to the material surfaces to be joined. Chromic acid anodising and phosphoric acid anodising are two known treatments currently in use with aluminium alloys and which confer good durability properties on the resulting joint. However, in some circumstances such as in repair work, it is not always feasible to apply chromic acid anodising or phosphoric acid anodising treatments and some other durability improving treatment is required which will have a performance approaching that of anodised and primed surfaces as made during initial manufacture.
There is thus a need for a process for improving the durability of a bonded aluminium alloy and/or ALCLAD (Trade Mark) material joint which preferably can be utilised for repair work where chromic acid anodising and phosphoric acid anodising treatments are not feasible or are environmentally toxic.